BRUSSELS, April 2: Russian Foreign Minister Sergei Lavrov lashed out on Friday as Nato welcomed seven ex-communist countries into its ranks in a historic enlargement that takes the alliance up to Russia's borders.

"We didn't want this enlargement, and we will continue to maintain a negative attitude. It's a mistake," Lavrov told reporters after Nato-Russia talks that followed the enlargement ceremony in Brussels.

"The presence of American soldiers on our border has created a kind of paranoia in Russia," he added after the talks with Nato foreign ministers, including US Secretary of State Colin Powell.

Moscow has been particularly incensed at the inclusion in Nato of the Baltic states Estonia, Latvia and Lithuania, which are all former Soviet republics.

Russia warned on Monday that it may be forced to beef up its own defences along the Baltic border in a move reminiscent of the Soviet Union's standoff with the US-led alliance during the Cold War.

With Nato F-16s starting patrols of the Baltic trio's airspace this week, Russia went as far as to warn of a possible "military response".

The North Atlantic Treaty Organisation and Russia are also embroiled in a row over the Conventional Forces in Europe (CFE) treaty, which limits troop numbers in eastern Europe.

The Baltic republics and Slovenia were not independent states when the CFE was signed in 1989 and Russia says the new Nato members will now have to join the treaty, and keep to its guidelines until they do.

The foreign minister also reaffirmed Moscow's concern about the rights of ethnic Russians in the Baltic countries, which along with seven other countries are also due to join the European Union on May 1.-AFP